A reduced domain pool based on DCT for a fast fractal image encoding

Fractal image compression is time consuming due to the search of the matching between range and domain blocks. In order to improve this compression method, we propose firstly, in this paper, a fast method for reducing the computational complexity of fractal encoding by reducing the size of the domain pool. This reduction is based on the lowest horizontal and vertical DCT coefficients of domain blocks. The experimental results on the test images show that the proposed method reduce the time computation and reach a high speedup factor without decreasing the image quality. Secondly, we combine our method to the AP2D approach which uses two domain pools in two steps of encoding. A more reduction of encoding time is obtained without decreasing the image quality

DEGRADATION OF CZECHOSLOVAK CREEP RESISTANT STEELS AFTER 50 YEARS OF SERVICE

Thermally loaded assemblies in the energy and chemical industries require materials that provide the necessary functional characteristics, even after very long periods of operation. For the assessment of these materials are used expression grade of degradation in the basic meaning of the original English word grade = quality grade, Where the degradation is cumulative deterioration of quality (properties) and thereby reduce the utility value. Knowledge of these mechanisms acting simultaneously allows determining the boundary conditions and more efficient utilization of used materials. Alternatively, it may give information to a qualified estimate of the causes of failure. Degradation starts its own production of semi-finished products (purity, structural homogeneity) continues through technological factors of production (welding) and the last part of degradation is during service of the parts (corrosion, hydrogen embrittlement, etc.). The aim of this article is at bases information obtained from fifty years of degraded materials to obtain information for more accurate reference catalogue. This catalogue can on bases information obtained from the microstructure and hardness estimate the state of degradation or possible time to rupture for the material

Influence of Cavity Shape on Discharge Activity in Solid Electrical Insulation Materials

Tato bakalářská práce se zabývá problematikou částečných výbojů se zaměřením na porovnání parametrů těchto výbojů v závislosti na rozměrech defektu v PET-G materiálu. V prvé části je kladen důraz na popis problematiky, vzniku a důsledků výskytu částečných výbojů. Elektrickým i neelektrickým metodám detekce částečných výbojů je společně s modelováním výbojů ve střídavém elektrickém poli věnována druhá část. V této části je popsán i Niemeyerův matematický model pro výpočet elektrických parametrů částečných výbojů, jehož výsledky jsou porovnány s výsledky z měření v praktické části. Praktická část má za cíl popsat jednotlivé vzorky, v nichž se nachází dutinky o různých rozměrech, a po přiložení střídavého napětí změřit elektrické parametry částečných výbojů vyskytujících se v dutinkách. V závěrečné části jsou výsledky porovnány s předpoklady z Niemeyerova matematického modelu a popsány efekty projevující se na paternu částečných výbojů v závislosti na různých rozměrech dutinek ve vzorcích.This bachelor thesis deals with partial discharges with a focus on comparing the parameters of these discharges depending on the dimensions of the defect in the PET-G material. In the first part, the emphasis is placed on describing the problems, origin, and consequences of partial discharges. The second part is devoted to electric and non-electric methods of detecting partial discharges and modeling discharges in alternating electric fields. This part also describes Niemeyer's mathematical model for calculating the electrical parameters of partial discharges, which are compared with the results of measurements in the practical part. The practical part aims to describe individual samples. There are cavities of different dimensions, and after applying an alternating voltage to measure the electrical parameters of partial discharges occurring in the cavities. In the final part, the results are compared with the Niemeyer mathematical model's assumptions and described the effects on the pattern of partial discharges depending on the different dimensions of the samples' cavities

DEGRADATION OF CZECHOSLOVAK CREEP RESISTANT STEELS AFTER 50 YEARS OF SERVICE

Thermally loaded assemblies in the energy and chemical industries require materials that provide the necessary functional characteristics, even after very long periods of operation. For the assessment of these materials are used expression grade of degradation in the basic meaning of the original English word grade = quality grade, Where the degradation is cumulative deterioration of quality (properties) and thereby reduce the utility value. Knowledge of these mechanisms acting simultaneously allows determining the boundary conditions and more efficient utilization of used materials. Alternatively, it may give information to a qualified estimate of the causes of failure. Degradation starts its own production of semi-finished products (purity, structural homogeneity) continues through technological factors of production (welding) and the last part of degradation is during service of the parts (corrosion, hydrogen embrittlement, etc.). The aim of this article is at bases information obtained from fifty years of degraded materials to obtain information for more accurate reference catalogue. This catalogue can on bases information obtained from the microstructure and hardness estimate the state of degradation or possible time to rupture for the material

Cardiorespiratory Fitness, Metabolic Risk, and Inflammation in Children

The aim of this study was to investigate the independent associations among cardiorespiratory fitness, metabolic syndrome (MetS), and C-reactive protein (CRP) in children. The sample consisted of 112 children (11.4  ±  0.4 years). Data was obtained for children's anthropometry, cardiorespiratory fitness, MetS components, and CRP levels. MetS was defined using criteria analogous to the Adult Treatment Panel III definition. A MetS risk score was also computed. Prevalence of the MetS was 5.4%, without gender differences. Subjects with low fitness showed significantly higher MetS risk (P < 0.001) and CRP (P < 0.007), compared to the high-fitness pupils. However, differences in MetS risk, and CRP between fitness groups decreased when adjusted for waist circumference. These data indicate that the mechanisms linking cardiorespiratory fitness, MetS risk and inflammation in children are extensively affected by obesity. Intervention strategies aiming at reducing obesity and improving cardiorespiratory fitness in childhood might contribute to the prevention of the MetS in adulthood

Pouzdanost i valjanost modoficiranoga terenskog testa za procjenu aerobne sposobnosti

The purpose of this study was to assess the reliability and the validity of a modified version of the Multi-stage Shuttle-Run Aerobic Test 20m. The proposed version is a hexagon with 10m side distances each named Hexagon Multi-Level Running Aerobic Test 10m. The same parameters (ending level, maximum speed and heart rate at the finish) were measured and the VO2max was estimated in both tests using the Multistage Shuttle-Run Aerobic Test 20m protocol and tables. For the proposed test the reliability evaluation was applied on a sample of 18 students (age 20.8±0.9yrs) twice with a 48h time interval, giving high correlations in maximum speed and VO2max (r=0.99) and ending level (r=0.98). For the Hexagon Multi-Level Running Aerobic Test 10m the validity assessment of the measured variables of this test were compared with the same variables of the Multistage Shuttle-Run Aerobic Test 20m in 62 trained adolescents (age 13.7±0.7yrs). The validity coefficients for all the variables between the two tests were r=0.86 (p<0.01). Furthermore, the participants’ performance profile was significantly higher in the proposed version, (p<0.05) while the mean VO2max of adolescents was significantly higher in this test than in the prototype Multistage Shuttle-Run Aerobic Test 20m (46±6.2 vs 40.8±4.9ml/kg • min), (p<0.05). Conclusively, it can be inferred that the Hexagon Multi-Level Running Aerobic Test 10m is not only a reliable and easy to use test but also, compared to the valid Multistage Shuttle-Run Aerobic Test 20m, it can be an objective test for the evaluation of aerobic performance in adolescents.Uvod Tijekom posljednja tri desetljeća pojavio se povećan interes za mjerenje aerobnih sposobnosti na razini populacije. Do danas su se te fiziološke karakteristike pretežno određivale primjenom laboratorijskih mjerenja, poput submaksimalnih ili maksimalnih testova na bicikl-ergometru ili pokretnom sagu. Nasuprot tome, terensko testiranje je jedino rješenje u kojem znanstvenik može učinkovito simulirati sportske situacije. Cilj je ovog istraživanja bio ocijeniti pouzdanost i valjanost modificirane verzije višestupanjskog aerobnog testa izmjeničnog trčanja na 20 metara (Multistage Shuttle-Run Aerobic Test 20m - MSRAT20m). Metode Predložena verzija je šesterokut sa svakom stranicom duljine od 10 metara. Test je nazvan šesterokutni višerazinski aerobni test trčanja na 10 metara (Hexagon Multilevel Running Aerobic Test 10m - HMRAT10m). Da bi se opravdalo razvijanje modificiranog terenskog testa, ocijenjeni su HMRA-T10m test-retest koeficijenti pouzdanosti i valjanosti parametara mjerenih testom HMRAT10m s istim parametrima MSRAT20m testa. U oba testa (MSRAT2-0m i HMRAT10m) je korištenjem MSRAT20m protokola izmjerena završna razina, maksimalna brzina i frekvencija srca u završnoj točki, a procijenjen je i maksimalni primitak kisika (VO2max) (Ramsbottom, Brewer, Williams, 1988). U evaluaciji pouzdanosti HMRAT10m, predložena verzija testa primijenjena je na uzorku od 18 studenata kineziologije (10 mladića i 8 djevojaka) u dobi od 20.8±0,9 godina. Test je izveden dva puta, s intervalom od 48 sati između dva izvođenja. Završna razina HMRAT10m dala je izvrsnu IC korelaciju (0,99) u oba izvođenja (8,1 vs 8,3). Slično tome, visoka IC korelacija opažena je između dva izvođenja tijekom oba HMRAT10m testa pri maksimalnoj brzini u završnoj točci (0,99), što odgovara brzini koju su studenti postigli na posljednjoj uspješno izvedenoj razini testa (12 vs 12,1km/h). Uz to, VO2max (47,2±9,1 vs 47,6±9,3 ml/kg•min), procijenjen na temelju tablica MSRAT20m protokola, u oba je HMRAT10m testa pokazao koeficijent pouzdanosti od 0,99. Za razliku od toga, za vršnu je frekvenciju srca u izvođenju oba HMRAT10m testa koeficijent pouzdanosti bio prihvatljiv (0,77), dok su se srednje vrijednosti vršne frekvencije srca ispitanika kretale u rasponu od 191±8.1b/min u prvom HMRAT10m testu, do 194±,4 b/min u drugom HMRAT10m testu. Osim ocjene pouzdanosti testa HMRAT10m, bilo je nužno dobiti koeficijente korelacije između varijabli modificirane verzije i varijabli mjerenih već valjanim testom. Za evaluaciju valjanosti HMRAT10m parametri ovog testa uspoređeni su s istim parametrima MSRAT20m testa kod 62 trenira-na adolescenta (39 mladića i 23 djevojke), u dobi od 13,7±0,7 godina. Rezultati U ocjeni valjanosti mjerenih parametara predstavljene modificirane verzije na razini odustajanja ili na završnoj razini testa, maksimalna brzina u završnoj točki i VO2max u oba HMRAT10m i MSRAT20m testa pokazali su koeficijente korelacije do razine od r=0,86, (p<0,01), dok je fiziološka varijabla frekvencije srca u završnoj točki oba testa pokazala nisku korelaciju (r=0,33, p<0,01). Parametri aerobne sposobnosti adolescenata u HMRAT10m testu, u odnosu na parametre u MSRAT20m testu, bili su 31,7% bolji na završnoj razini, 9% viši kod maksimalne brzine u završnoj točci i 11,3% veći u VO2max, što je možda i najjači dokaz ovog istraživanja. Uzimajući u obzir da je vršna frekvencija srca ispitanika u završnoj točki, kao pokazatelj maksimalnog napora ispitanika, bila prilično slična u oba testa, možemo pretpostaviti da HMRAT10m pokazuje bolje maksimalne aerobne sposobnosti od MSRAT20m. Normaliziranjem rezultata prema spolu, dobili smo podatke da su adolescenti muškog spola pokazali bolje rezultate tijekom HMRAT10m od djevojaka, u odnosu na MSRAT20m, izuzevši vršnu frekvenciju srca u završnoj točki, u kojoj su i mladići i djevojke imali slične vrijednosti. Štoviše, usporedbe ispitanika prema spolu u ovom istraživanju potvrđuju da su u svim mjerenim varijablama mladići imali bolji aerobni profil od djevojaka u oba testa te su, posljedično, adolescenti muškog spola imali bolje aerobne rezultate od djevojaka u testu HMRAT10m. Zaključci U zaključku, HMRAT10m test za procjenu aerobne sposobnosti dizajniran je da kinematički premosti jaz između intermitentne naizmjenične osobine MSRAT20m testa i kružne trkačke osobine terenskih testova izdržljivosti koji se izvode na stazi, sa stalnom ili progresivno rastućom brzinom trčanja. Prevladavanje korelacija pouzdanosti HMRA-T10m testa u odnosu na njegove visoke koeficijente valjanosti, u usporedbi s već postojećim valjanim i dobro prihvaćenim MSRAT20m testom, moglo bi ovaj test ponuditi kao alternativni oblik procjene VO2max. Daljnja istraživanja, koja bi u uvjetima istraživačkih laboratorija evaluirala koeficijente valjanosti aerobnih rezultata HMRAT10m testa u vidu VO2max, mogla bi HMRAT10m test definirati kao novi, valjan i dobro prihvaćen terenski test, s vlastitim jednadžbama za procjenu aerobne sposobnosti za različite dobne skupine, populacije i različite sportove

SP-D counteracts GM-CSF-mediated increase of granuloma formation by alveolar macrophages in lysinuric protein intolerance

<p>Abstract</p> <p>Background</p> <p>Pulmonary alveolar proteinosis (PAP) is a syndrome with multiple etiologies and is often deadly in lysinuric protein intolerance (LPI). At present, PAP is treated by whole lung lavage or with granulocyte/monocyte colony stimulating factor (GM-CSF); however, the effectiveness of GM-CSF in treating LPI associated PAP is uncertain. We hypothesized that GM-CSF and surfactant protein D (SP-D) would enhance the clearance of proteins and dying cells that are typically present in the airways of PAP lungs.</p> <p>Methods</p> <p>Cells and cell-free supernatant of therapeutic bronchoalveolar lavage fluid (BALF) of a two-year-old patient with LPI were isolated on multiple occasions. Diagnostic BALF samples from an age-matched patient with bronchitis or adult PAP patients were used as controls. SP-D and total protein content of the supernatants were determined by BCA assays and Western blots, respectively. Cholesterol content was determined by a calorimetic assay or Oil Red O staining of cytospin preparations. The cells and surfactant lipids were also analyzed by transmission electron microscopy. Uptake of Alexa-647 conjugated BSA and DiI-labelled apoptotic Jurkat T-cells by BAL cells were studied separately in the presence or absence of SP-D (1 μg/ml) and/or GM-CSF (10 ng/ml), <it>ex vivo</it>. Specimens were analyzed by light and fluorescence microscopy.</p> <p>Results</p> <p>Here we show that large amounts of cholesterol, and large numbers of cholesterol crystals, dying cells, and lipid-laden foamy alveolar macrophages were present in the airways of the LPI patient. Although SP-D is present, its bioavailability is low in the airways. SP-D was partially degraded and entrapped in the unusual surfactant lipid tubules with circular lattice, <it>in vivo</it>. We also show that supplementing SP-D and GM-CSF increases the uptake of protein and dying cells by healthy LPI alveolar macrophages, <it>ex vivo</it>. Serendipitously, we found that these cells spontaneously generated granulomas, <it>ex vivo</it>, and GM-CSF treatment drastically increased the number of granulomas whereas SP-D treatment counteracted the adverse effect of GM-CSF.</p> <p>Conclusions</p> <p>We propose that increased GM-CSF and decreased bioavailability of SP-D may promote granuloma formation in LPI, and GM-CSF may not be suitable for treating PAP in LPI. To improve the lung condition of LPI patients with PAP, it would be useful to explore alternative therapies for increasing dead cell clearance while decreasing cholesterol content in the airways.</p

Effect of Arginase Inhibition on Pulmonary L-Arginine Metabolism in Murine Pseudomonas Pneumonia

Rationale: Infection of the lung with Pseudomonas aeruginosa results in upregulation of nitric oxide synthases (NOS) and arginase expression, and both enzymes compete for L-arginine as substrate. Nitric oxide (NO) production may be regulated by arginase as it controls L-arginine availability for NOS. We here studied the effect of systemic arginase inhibition on pulmonary L-arginine metabolism in Pseudomonas pneumonia in the mouse. Methods: Mice (C57BL/6, 8–10 weeks old, female) underwent direct tracheal instillation of Pseudomonas (PAO-1)-coated agar beads and were treated by repeated intra-peritoneal injections of the arginase inhibitor 2(S)-amino-6-boronohexanoic acid (ABH) or PBS until lungs were harvested on day 3 of the infection. L-arginine metabolites were quantified using liquid chromatography-tandem mass spectrometry, NO metabolites nitrate and nitrite by Griess reagent and cytokines by ELISA. Results: NO metabolite concentrations (48.5±2.9 vs. 10.9±2.3 µM, p<0.0001), as well as L-ornithine (29.6±1.7 vs 2.3±0.4 µM, p<0.0001), the product of arginase activity, were increased in Pseudomonas infected lungs compared to naïve controls. Concentrations of the NOS inhibitor asymmetric dimethylarginine (ADMA) were also increased (0.44±0.02 vs. 0.16±0.01 µM, p<0.0001). Arginase inhibition in the infected animals resulted in a significant decrease in L-ornithine (14.6±1.6 µM, p<0.0001) but increase in L-arginine concentration (p<0.001), L-arginine/ADMA ratio (p<0.001), L-arginine availability for NOS (p<0.001), and NO metabolite concentrations (67.3±5.7 µM, p<0.05). Arginase inhibitor treatment also resulted in an increase in NO metabolite levels in animals following intratracheal injection of LPS (p = 0.015). Arginase inhibition was not associated with an increase in inflammatory markers (IFN-γ, IL-1β, IL-6, MIP-2, KC or TNF-α) in lung. Concentrations of the L-ornithine-dependent polyamines putrescine, spermidine and spermine were increased in Pseudomonas infected lungs (p<0.001, respectively) but were unaffected by ABH treatment. Conclusions: Systemic arginase inhibition with ABH during Pseudomonas pneumonia in mice results in an increase in pulmonary NO formation but no pro-inflammatory effect

In situ and low-cost monitoring of particles falling from freshwater animals: from microplastics to parasites

A simple and low-cost method of monitoring and collecting particulate matter detaching from (or interacting with) aquatic animals is described using a novel device based on an airlift pump principle applied to floating cages. The efficiency of the technique in particle collection is demonstrated using polyethylene microspheres interacting with a cyprinid fish (Carassius carassius) and a temporarily parasitic stage (glochidia) of an endangered freshwater mussel (Margaritifera margaritifera) dropping from experimentally infested host fish (Salmo trutta). The technique enables the monitoring of temporal dynamics of particle detachment and their continuous collection both in the laboratory and in situ, allowing the experimental animals to be kept under natural water quality regimes and reducing the need for handling and transport. The technique can improve the representativeness of current experimental methods used in the fields of environmental parasitology, animal feeding ecology and microplastic pathway studies in aquatic environments. In particular, it makes it accessible to study the physiological compatibility of glochidia and their hosts, which is an essential but understudied autecological feature in mussel conservation programs worldwide. Field placement of the technique can also aid in outreach programs with pay-offs in the increase of scientific literacy of citizens concerning neglected issues such as the importance of fish hosts for the conservation of freshwater mussels.We thank Zbyněk Janči and Bohumil Dort for the help in the field, the nature conservation authorities for providing permits and access to the research area in Borová Lada and two anonymous reviewers for their helpful comments on an earlier draft. All experiments were in compliance with the current laws of the Czech Republic Act No. 246/1992 coll. on the protection of animals against cruelty